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Parts Where to get, and how to make the best bits. PCB's, caps, transformers, etc.

My Transistors, original or copy?
My Transistors, original or copy?
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Old 18th March 2018, 04:14 PM   #971
davada is offline davada  Canada
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Join Date: Jul 2004
Location: Fort St John, BC Canada
I had a local shop in Vancouver BC I purchased parts from on a regular basis for my repair shop. One day I got back to the shop to find a transistor in a metal TO3. The transistor number was only ever made for TO220.

I got suspicious when one day they told me they could get MJ15024/25 out of a vendor in Germany cheaper than buying them USA including freight.

These guys were not dishonest but they were in denial. They just wouldn't believe one of there vendors would sell them fake parts. I heard from them a few years later they threw a guy out of their shop for accusing them of selling fake parts.

Some vendors just stick their heads in the sand when it comes to fake parts. Who has time to test and verify ever single transistor that comes through the door.

It's a very sensitive issue for vendors. I think it might be best to simply tell them the part doesn't meet spec and let them deal with it or communicate it in some other non accusing way.
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Old 18th March 2018, 04:57 PM   #972
jlithen is offline jlithen  Finland
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Quote:
Originally Posted by kees52 View Post
I get opa2604 but I am afraid these are not original because there are signs it is reprinted.

better picture I can not make. Came from eleleparts ebay seller from china.

regards
They do not look bad in the photo, but looking at the sellers prices (fraction of official dealer cost) they are probably fake I'd say.

And yes, many sellers live in denial, like Kessler never understood that their bad looking parts, far outside specs, really could be fake!
What worries me even more is that they kept selling them after I won the case.
On ebay I think feedback is the most powerful tool. Listings will not be removed just because buyers (and experts) claim that item is fake.

And also yes to never accusing seller of selling fakes (except on forums like this). I learned it the hard way. Simply claim them for being not-working. Then you can return them at sellers or PayPal's cost.
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Old 18th March 2018, 05:55 PM   #973
asuslover is offline asuslover  Romania
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My Transistors, original or copy?
Picture is blurry .
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Old 18th March 2018, 06:04 PM   #974
WalterW is offline WalterW  Netherlands
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My Transistors, original or copy?
Quote:
Originally Posted by jlithen View Post
And yes, many sellers live in denial, like Kessler never understood that their bad looking parts, far outside specs, really could be fake!
Ah, Thanks! Just wanted to order a few 2Sk364 and 2SK369's there.
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Old 21st March 2018, 08:17 PM   #975
WalterW is offline WalterW  Netherlands
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My Transistors, original or copy?
Today I received a package from NicMac who sold the strange looking Toshiba's JFET's.
In it was one 2SK170BL and one 2SJ74BL.
I have measured them both and compared them to a matching Idss JFETs from my personal stock.
And sorry NicMac, you are right, they are real Toshiba's!
Tomorrow they are both going back to Italy


The JFET body is exactly the same size, pins are the same, the stripe at the top is in the middle. They look good. When I place them in my test jig Idss rises also, which is good.


Have a look at the numbers, I measured the Id - Vgs in 50mV steps.
The Toshibas are cut-off at around 500mV that is according to the datasheet. See picture what I measured.
Look at the fake it is cut-off at 750mV! and Idss is above spec.
Attached Images
File Type: jpg Curve.jpg (81.0 KB, 155 views)
File Type: jpg JFETS NicMac.jpg (101.2 KB, 138 views)
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Old 21st March 2018, 08:20 PM   #976
NicMac is offline NicMac  Italy
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My Transistors, original or copy?
Quote:
Originally Posted by WalterW View Post
Tomorrow they are both going back to Italy
Keep them as a souvenir
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Old 21st March 2018, 08:44 PM   #977
jlithen is offline jlithen  Finland
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Quote:
Originally Posted by WalterW View Post
Ah, Thanks! Just wanted to order a few 2Sk364 and 2SK369's there.
I think their 2SK364 were genuine and 2SK363 were fake. Also watch out for their "Japan Transistor" items which are ISC
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Old 21st March 2018, 08:44 PM   #978
WalterW is offline WalterW  Netherlands
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My Transistors, original or copy?
haha, no I have plenty of them BL's, maybe you can make a match with others and sell them.
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Old 21st March 2018, 08:45 PM   #979
WalterW is offline WalterW  Netherlands
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My Transistors, original or copy?
Quote:
Originally Posted by jlithen View Post
I think their 2SK364 were genuine and 2SK363 were fake. Also watch out for their "Japan Transistor" items which are ISC
What is ISC?
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Pass F5, F5Tv3, ACA, Aleph J, DDDAC1794, DCB1, BA3-preamp, VFET CSX1, Pass F6, Pass M2-HPA, VFET-X balanced, Pass J2
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Old 21st March 2018, 09:25 PM   #980
jlithen is offline jlithen  Finland
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Quote:
Originally Posted by WalterW View Post
What is ISC?
Inchange Semiconductor Company = inferior parts
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